package com.lagou.homework2;

public class PhoneTest {

    public static void main(String[] args) {
        CellPhone op = new OldPhone();
        CellPhone np = new NewPhone();
        op.call();
        op.text();
        np.call();
        np.text();
        np.playGame();
        op.playGame();//值为空
    }
}
